1. Field of the Invention
This invention relates to a system, as well as method of operation thereof, for providing air condition utility to buildings throughout districts using an assigned station per district for circulating refrigerant to and from each building while deleting any need for self-contained condensing units by buildings.
2. Description of the Prior Art
Any discussion of a system for providing air condition utility from a station to a number of locations arouses several major issues.
Obviously, required expenses are among the primary issues that appear. Usually, expenses for presently-used air conditioning systems are high and unnecessary. A main contributor to expenses for presently-used air conditioning systems is a self-contained condensing unit which is frequently positioned on roofs of buildings. Said self-contained condensing unit conditions air through a network of ducts and, using some air distribution means, distributes the conditioned air to a plurality of chambers or zones. A version of a frequently used self-contained condensing unit is a terminal fan coil unit which is generally positioned in a wall of a room or of a zone to be provided with conditioned air. Said terminal fan coil is adapted to withdraw "used" air (or secondary air) from the room or zone for further conditioning prior to being recirculated upon mixing with fresh or primary air.
An attempt to reduce cost of installing, repairing and replacing self-contained condensing units and to expand the field of application of said units has resulted in an increase in popularity of ducted cooling systems using ducted incremental units. As a result, unit air conditioners are presently each installed at a single location with ducts extending laterally to remote locations in order to provide more uniform and effective air conditioning in a number of zones. A disadvantage of said existing ducted cooling systems is due to withdrawal of return air from the cooled room or region at the condensing unit only. The return air withdrawal requires greater air induction in the vicinity of the condensing unit, causing draughty conditions within the cooled room or region. In addition to requiring substantially increased labor costs for fabrication and installation of separate supply and return air ducts, the existing ducted cooling systems require costly modifications of their central air condensing unit and terminal fan coil units in each room or region to be air conditioned.
Various types of systems for distribution of fluids and/or aiming at cooling have been developed in the past. However, due to high costs and lack of efficiency, these systems have not been capable of providing air condition utility for a populated area.
Gatling, U.S. Pat. No. 4,495,781, issued on Jan. 29, 1985, patents an underground air cooling system for at least one building. The cooling system includes an air line disposed beneath the ground for conveying air to an I-tank having an upper and a lower compartment. A fluid filling the lower compartment of the I-tank absorbs heat from the air in the air line and dissipates that heat quickly to the surrounding earth and to the fluid in the upper compartment of the I-tank. Also, a fluid line is connected to the I-tank and is interposed in the path of the air in the air line. Cold water from the I-tank runs through the water line. When air passes over the fluid line in the air line, the air is cooled and dehumidified before reaching a building.
Bennett, U.S. Pat. No. 3,817,159, issued on Jun. 18, 1974, patents a ducted air conditioning system for providing conditioned air to a plurality of zones and a combination duct for the system. A combination supply and return air duct connects the fan coil unit of either an incremental air conditioner or a central system with each of the zones to be supplied with conditioned air. The combination duct forms supply and return air sections that are almost completely sealed from each other. Each section has a plurality of openings connecting the section to the surrounding environment. The return air section communicates with the fan coil unit for recycling of the return air to the unit.
Newton, U.S. Pat. No. 3,425,485, registered on Feb. 4, 1969, discusses an air conditioning unit and pump for single pipe system. The water supplied to the units is circulated through a heat exchanger in the air handling units by means of a pump which is intermittently operated. The pump operates only if the room requires cooling and chilled water is available and when the room requires heating and heated water is available.
The above-listed systems and many other distribution systems exist in different industries. However, few of these systems are capable of distributing air condition utility to buildings throughout a district using a station for circulating refrigerant to and from each building. A cooling system, as well as method of operation thereof, is described herein that provides air conditioning to buildings and deletes any need for individual condensing units.